Method of and apparatus for electrically heating metal



(No Model.) 2 Sheets-Sheet l.

G. D. BURTON. METHOD OF AND APPARATUS FOR ELEGTRIGALLY HEATING METAL. No. 537,007. Patented Apr. 9, 1895. A

(No Model.) 2 Sheets-Sheet 2.

G. D. BURTON. METHOD OF AND APPARATUSTOR ELECTRICALLY HEATING METAL. No. 537,007. Patented Apr. 9, 1895.

UNITED STATES PATENT ()FFICE.

GEORGE D. BURTON, OF BOSTON, MASSACHUSETTS.

METHOD OF AND APPARATUS FOR ELECTRICALLY HEATING METAL.

SPECIFICATION forming part of Letters Patent No. 537,007, dated April 9, 1895.

Application filed January 23,1895. Serial No. 535,981. (No model.)

To all whom it may concern:

Be it known that I, GEORGE D. BURTON, a citizen of the United States of America, residing at Boston, in the county of Suffolk, in the State of Massachusetts, have invented certain new and useful Improvementsin Methods of and Apparatus for Electrically Heating Metals, of which the following is a specification.-

This invention relates to the heating of metals, for forging, melting, smelting or other purposes, by the use of an electrolytic bath and an electric are formed in connection therewith.

The invention consists as regards the method in the art of heating metal whether embodied in ore in a natural state, or in metallic or alloy form, or shaped into a manufactured article, by resting the metal upon the surface of a non-conductive bed above the surface of an electrolytic bath, then shifting vertically the horizontal plane of one of said surfaces and bringing the bath and the metal into electric connection, and passing an electric current through the metal and bath, said current forming an electric are or arcs between the metal and the liquid of the bath.

The invention consists as regards the apparatus principally in the combination of a vessel for containing the electrolytic bath, a non-conductive bed for the metal to be heated, the surface of said bed being in a plane above the surface of the bath in their normal relations, means for elevating and depressing one of said surfaces to bring the bath and the metal on the bed into electric connection and separate them at will, and conductors for connecting said bath and metal with opposite electric poles.

The invention consists further in a nonconductive bed having a roughened surface in combination with the other elements as above set forth.

The invention further consists in certain details of construction hereinafter claimed.

Figure 1 of the accompanying drawings represents a vertical longitudinal section of the apparatus constituting a part of this invention. Fig. 2 represents a plan view thereof.

Fig. 3 represents a vertical longitudinal section of the apparatus, showing another form of actuator for the bath elevating mechanism.

conductive bed for the metal to be heated,

melted or smelted.

The same reference-numerals indicate the same parts in all the figures.

This apparatus comprises a vessel for containing an electrolytic solution 20. This vessel, preferably in the form of a tank, is constructed of or lined with material which is a non-c0nductor of electricity. It is preferably composed of porcelain or fire clay or earthenware lined with porcelain; and to protect it against breakage it is surrounded by a wooden jacket 11.

An electrolytic bath is disposed in the tank 10 and partially fills said tank. This bath consists of any suitable electrolyte, being one which will cause with the electric current under proper conditions, the formation of a voltaic are between the metal to be heated and the liquid. The electrolyte should have a specific gravity greater than that of water and it may consist of an acid or an alkaline watery solution, preferably thelatter. A solution of sal soda of a specific gravity of 1.305 at 84 Fahrenheit answers the purpose effectually; also a solution of equal parts of sal soda and cream of tartar of a specific gravity of 1.255 at 77 Fahrenheit; also asolution composed of water, carbonate of soda and borax in the proportions of three quarts of water to twelve pounds of carbonate of soda and one pound of borax.

An anode plate is disposed in the tank and has a contact surface with the liquid, much greater than the area of contact of the article to be heated. This plate is composed of lead, copper, carbon or other suitable conductive material and it is preferably in angular form, one part resting on the bottom of the tank and the other part being parallel with one end thereof. A fixed rod 31 extends from said plate to the top of the tank being provided with a binding post 82, and a conductor 33 is secured in said binding post and connected at its other end to a positive pole of an electric source.

A conductive rest is disposed at one side or one end of the tank, being preferably supported in brackets as 41 secured to one end of the tank. A conductor a5 is secured at one end to this conductive bed and is connected at its other end to the negative pole of an electric source.

A work bed 50 for the metal to be heated is disposed in the tank 10 and its surface 51 is normally above the plane of the surface of the bath 20. This work rest is composed of non-conductive material, such as fire clay, stone, or slate, preferably the latter. Its upper surface 51 is preferably corrugated, serrated or otherwise roughened in some way so that parts thereof are elevated above other parts. This non-condnctive bed serves as a rest for the metal to be heated and its corrugated or roughened surface permits the liquid to intervene between the metal and the bed, whereby an are or arcs are formed on the under side of the metal.

A conductor 60 serves to connect the metal on the work bed 50 with the negative pole of the electric source, said conductor bearing upon the conductive rest 45 through which the current passes. This conductor 60 is preferablyin the form of a pairof tongs, the jaws grasping or touching the metal to be heated, and the handles being disposed in contactwith said rest.

As before stated, the surface of the work bed 50 is normally above the surface of the bath 20, and any suitable means are provided for shifting vertically one of said surfaces with reference to the other so that the metal on the bed and the liquid of the bath are brought into electrical connection. In the instance illustrated in the accompanying drawings the surface of the bath is elevated and depressed relatively to the surface of the bed. Any suitable means may be employed for this purpose. The means herein shown comprise a plunger barrel opening into the tank 10, and preferably formed within the tank by a partition 12 dividing off a portion of said tank, and a plunger 71 adapted to fit and play within this plunger barrel. A red 72 connected with said plunger extends through a stuffing box 14 in the bottom of the tank, and is connected at its lower end to the slotted end of an actuating lever 73, which is preferably in the form of a pedal lever pivoted on a suitable support, as 74. In the construction shown in Fig. 3 a plunger rod 75 connects with the slotted inner end of a lever 76 pivoted to a bracket 77 attached to one end of the tank and a rod 78 connects the outer end of said lever with the pedal lever 73.

In the use of this apparatus, as shown in Figs. 1 and 2, for carrying out the method described, the metal to be heated, as for instance a horse shoe 100, is placed on the work bed 50 by means of a pair of tongs 60, the handles thereof being in contact with the conductive rest 40, and the jaws being in contact with the metal. Then the pedal 73, or other actuating device, is depressed sufficiently to cause the plunger 71 to elevate the surface of the liquid so as to first submerge the metal on the bed 50 and wet its entire surface, and then the pedal is slightly raised so that the surface of the liquid is lowered to merely form contact with the under side of the metal on the bed or to a point sufficiently near to said metal to maintain an electric are between it and the liquid. This contact of the liquid with the metal closes the circuit and an electric are or arcs are formed between the metal and the liquid, which arcs serve to quickly heat the metal to a red, white or fusing temperature as desired.

The current used has a voltage of from one hundred and twenty to five hundred and an amperage of from six amperes upward according to the size or quantity of the metal being heated.

\Vhen the metal being heated is sufficiently heated to place it in the desired condition, the pedal orother actuating mechanism is released and the surface of the liquid is permitted to fall below the metal and it can then be removed and utilized as desired.

In Fig. 3, the fixed conductive rest connected with the negative pole is dispensed with and a tool as 80 similar to a soldering iron, is connected with the conductorSl leading to the negative pole of the electric source, and when the liquid is elevated into contact with the metal, as an article 200, to be heated on the work bed 50, this tool is brought into contact therewith and establishes a current and the are is formed.

This apparatus constitutes a very convenient forge for a blacksmith and also an economical one as no current is employed when the article is not being heated.

Ore may be placed upon the rest and the metal contained therein smelted and separated from the ore by placing a conductor as 80 in contact therewith or holding it in close proximity thereto, so that an electric arc is formed.

The term metal as used in the specification and claims is intended to include that substance in any form.

I claim as my invention- 1. The art of heating metal which consists in supporting the metal upon the surface of a non-conductive bed above the surface of an electrolytic bath, then shifting vertically the horizontal plane of one of said surfaces and bringing the bath and metal into electrical connection, and passing an electric current through the metal and bath, said current forming an electric are or ares between the metal and the liquid of the bath.

2. The art of heating metal, which consists in supporting it above the surface of an electrolytic bath, then elevating the surface of said bath into contact therewith, and passing an electric. current through said article and bath forming an electric are between them,

substantially as described.

3. The combination of a tank, an electrolytic bath therein, a non-conductive bed for the metal to be heated, the surface of said bed being above the surface of said bath in their normal relations, means for elevating and depressing one of said surfaces to bring the bath and metal on the bed into electric connection and separate them at will, and conductors for connecting said bath and metal with opposite electric poles.

4. The combination of a tank, an electrolytic bath therein, a non-conductive bed forthe metal to be heated provided with a roughened surface, the surface of said bed being above the surface of said bath in their normal relations, means for elevating and depressing one of said surfaces to bring the bath and metal on the bed into electric connection and separate them at will, and conductors for connecting said bath and metal with opposite electric poles.

5. The combination of a tank, an electrolytic bath disposed therein, a work bed provided with an irregular surface and disposed in saidbath for supporting the metal to be heated, means for elevating and depressing the surface of the bath relatively to said work bed, and electric conductors connected with opposite electric poles and respectively with said bath and metal.

6. The combination of a tank, an electrolytic bath disposed therein, a work bed provided with an irregular surface and disposed in said bath for supporting the metal to be heated, a plunger chamber, a plunger therein for elevating and depressing the surface of the bath, means for actuating said plunger, and electric conductors connected with opposite electric poles respectively.

7. The art of heating metal, which consists in supporting it above the surface of an electrolytic' bath, then elevating the surface of said bath into contact with the metal and permitting the metal or conductor connected therewith to protrude above the surface of the bath, and passing an electric current through said metal and bath, said current forming an electric are between them.

8. The combination of a vessel, an electrolytic bath therein, a non-conductive bed upon which that portion of the metal to be heated rests during the heating operation, the surface of said bed being above the surface of said bath in their normal relations, conductors for connecting said bath and metal with opposite electric poles, and means for elevating and depressing one of said surfaces to cause the liquid of the bath to overflow said bed, and to bring the bath and the metal on the bed into electrical connection and separate them at will.

GEO. D. BURTON.

Witnesses:

E. F. PHILIPSON, H. T. MARSHALL. 

